/////////////////////////////////////////////////////////////////////////////
// Original code from libhdfs3. Copyright (c) 2013 - 2014, Pivotal Inc.
// All rights reserved. Author: Zhanwei Wang
/////////////////////////////////////////////////////////////////////////////
//  Modifications by Kumo Inc.
// Copyright (C) Kumo inc. and its affiliates.
// Author: Jeff.li lijippy@163.com
// All rights reserved.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
//



#pragma once

#include <string>
#include <cassert>
#include <cstdio>
#include <string>
#include <vector>

namespace Hdfs {
namespace Internal {

class FileWrapper {
public:
    virtual ~FileWrapper() {
    }

    virtual bool open(int fd, bool delegate) = 0;
    virtual bool open(const std::string & path) = 0;
    virtual void close() = 0;
    virtual const char * read(std::vector<char> & buffer, int32_t size) = 0;
    virtual void copy(char * buffer, int32_t size) = 0;
    virtual void seek(int64_t position) = 0;
};

class CFileWrapper: public FileWrapper {
public:
    CFileWrapper();
    ~CFileWrapper();
    bool open(int fd, bool delegate);
    bool open(const std::string & path);
    void close();
    const char * read(std::vector<char> & buffer, int32_t size);
    void copy(char * buffer, int32_t size);
    void seek(int64_t offset);

private:
    FILE * file;
    std::string path;
};

class MappedFileWrapper: public FileWrapper {
public:
    MappedFileWrapper();
    ~MappedFileWrapper();
    bool open(int fd, bool delegate);
    bool open(const std::string & path);
    void close();
    const char * read(std::vector<char> & buffer, int32_t size);
    void copy(char * buffer, int32_t size);
    void seek(int64_t offset);

private:
    bool openInternal(int fd, bool delegate, size_t size);

private:
    bool delegate;
    const char * begin;
    const char * position;
    int fd;
    int64_t size;
    std::string path;
};

}
}
